Research conducted on cyclist's feet showed that 96% of us have forefeet that are canted or tilted up to the inside inward ("varus") or outward toward the outside ("valgus"). The vast majority (87%) of cyclist's feet tilt up to the inside. Unfortunately, almost all cycling shoes, cleats and pedals take this natural tilt and force it flat. This can generate knee pain, create a foot "hotspot" (where the inner or outer side of the foot feels hot) and diminish power.
In the Shoe (ITS) Wedges® provide 1.5 degrees of inward angulation (aka "varus") in cycling shoes that have ample room in the forefoot area. They are often used in conjunction with Cleat Wedges® or as a quick way of determining if inward or outward forefoot tilt or canting exists.
N.B. these items are sold individually.